1. Field of the Invention
This invention relates generally to a fuel supply device for a vehicle, and more particularly to a fuel supply device of the type in which a brushless motor is used as a drive motor for a fuel pump, and a control circuit for the brushless motor is integrated with the fuel pump and the motor so that the fuel supply device can be mounted within a fuel tank of the vehicle.
2. Background of the Art
There have heretofore been proposed fuel supply devices for a vehicle which use a brushless motor. For example, there is known a fuel supply device for a vehicle as disclosed in Japanese Utility Model Unexamined Publication No. 62-59794. In this conventional device, a control circuit for controlling the excitation of stator coils is accommodated within a container, and pressurized gas is sealed in this container, thus integrally providing the control circuit within a housing of a fuel pump.
In this conventional construction, since the control circuit is isolated from fuel, disadvantages, such as a conduction failure of the control circuit due to an electrolytic corrosion, and a short-circuiting of a circuit wiring, are prevented. In this conventional construction, however, wires connecting the control circuit to the stator coils are exposed to the fuel, and therefore, there has been a possibility that terminals connected to the control circuit, and the copper connection wires, and the stator coils may be subjected to an electrolytic corrosion, which results in a conduction failure and a short-circuiting.
Another problem with the conventional construction is that when its parts are to be mounted in the housing, the stator coils and the control circuit are connected together by the wires in a narrow space available within the housing, so that the efficiency of the assembling operation is poor.
The conventional construction suffers from a further problem in that since the stator coils and the control circuit are connected together by the wires when the parts are to be mounted in the housing, such connection portions are inevitably exposed to the fuel.